[iDMR] Flash driver on initialisation write-protects some sectors,

currently sectors 0-3. Sector 3 does not need to be protected, though
(U-boot occupies sectors 0-1 and the environment sector 2). This commit
fixes this, i.e., only sectors 0-2 are protected.

board/idmr/flash.c

@@ -97,7 +97,7 @@ unsigned long flash_init (void)
 
 	flash_protect (FLAG_PROTECT_SET,
 		       CFG_FLASH_BASE,
-		       CFG_FLASH_BASE + 0x30000, &flash_info[0]);
+		       CFG_FLASH_BASE + 0x2ffff, &flash_info[0]);
 
 	return size;
 }